Spin manipulation utilizing Weyl electrons in ferromagnetic SrRuO

Araki, Yasufumi   ; Ieda, Junichi   

Spintronics has been hindered by substantial power losses associated with the electric manipulation of spins. To mitigate Joule heating, we have developed a theory of electrically induced spin torques incorporating the topological structure of electron states. This topological contribution is free from dissipation and significantly enhances the torque efficiency per unit current compared with the conventional spin transfer torque. Our theory is supported by a magnetization switching experiment on ferromagnetic oxide SrRuO, where the observed torque is attributed to a type of topological electrons known as Weyl electrons.